OPTICAL SOUNDING III.
Abstract
Studies have been conducted utilizing simulated data of a ruby laser radar to study atmospheric water vapor profiles. Transfer equations have been evaluated incorporating 20 water vapor lines near 6943A. It is shown that the 6943.815A line stands essentially isolated in the telluric spectrum. An analysis is presented of the uncertainties in the deduced water profile obtained for simulated data based upon the 6943.815A line. It is shown that for the present laser radar, the uncertainty in the deduced water vapor density originated primarily in the uncertainty associated with the water vapor absorption coefficient. The Doppler-broadening of radiation scattered from aerosol particles or by Rayleigh scattering processes does not obey the spectral density shape predicted from the Maxwell-Boltzmann distribution of velocities for the particles or air molecules. As Dicke has pointed out, spectral narrowing can occur due to collisions. This phenomenon is discussed in relation to the Doppler spectrum of scattered radiation. The conclusions have been confirmed in experiments reported in the literature. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1967
- Accession Number
- AD0657601
Entities
People
- Alan Nathan
- James Bradley
- R. M. Schotland
Organizations
- New York University